Hi B4Bob,
What size did you order?
82" x 76" doesn’t match any of the standard sizes so I’m not clear what the dimensions of your mattress should be.
Although different manufacturers can have slight variances in their standard sizing … the ISPA (International Sleep Products Association) standard sizes are listed in post #2 here and a California King should be about 72" x 83.5" (+/- an inch) and an Eastern King size should be about 76" x 79.5" (again +/- an inch).
There have been a few members that have commented that it took longer than they expected for their mattress to reach it’s final dimensions but your measurements are a little unusual because in most cases the initial dimensions were slightly less than the standard dimensions for the first few days but the measurements you posted are both longer and narrower than an Eastern King would normally be and are the right width (within an inch) but shorter than a California King would normally be.
There is generally a break in and adjustment period with any new mattress over the course of the first few weeks as the foams in your mattress lose any of their “false firmness” and the cover loses any of its initial stiffness and you get used to the feel of a mattress that is different from the memory foam you were used to sleeping on so your experience can change over the course of the first few weeks.
Having said that … there are no “standard” definitions or consensus of opinions for firmness ratings and different manufacturers can rate their mattresses differently than others so a mattress that one manufacturer rates as being a specific firmness could be rated differently by another manufacturer. Different people can also have very different perceptions of firmness and softness compared to others as well and a mattress that feels medium for one person can feel like “firm” for someone else or “soft” for someone else (or vice versa) depending on their body type, sleeping style, physiology, their frame of reference based on what they are used to, and their individual sensitivity and perceptions. There are also different types of firmness and softness that different people may be sensitive to that can affect how they “rate” a mattress as well (see post #15 here). This is all relative and subjective and is as much an art as a science.
If your mattress is still firmer than you are comfortable with once you have slept on it for a few weeks then it’s possible that the firmness choice you made wasn’t the most suitable choice for you but of course that’s the reason for the 120 day trial period so you can test the mattress in your bedroom by actually sleeping on it instead of testing it in a showroom.
Thanks for taking the time to share your comments and feedback … I appreciate it. I’ll be interested in your follow up comments after you’ve talked with Brooklyn Bedding and of course about how the mattress feels to you once you’ve slept on it for a little longer as well.
Phoenix